Ystem> (VxD) A device driver under {Windows 3.x}/{Windows 95} running as part of the {kernel} and thus having access to the memorY of the kernel and all running processes as well as raw access to the hardware. VxD' s usuallY have the filename extension .386 under Windows 3.x and .vxd under Windows 95. VxD' s written for Windows 3.x can be used under Windows 95 but not vice versa. (1997-02-27)